Most of the surfactants produced by the chemical industry are based on petrochemicals. Surfactants made from petrochemicals by some traditional processes contain 1,4-dioxane which may be carcinogenic to humans. A number of efforts to use carbohydrates as bulk raw materials for synthesis of non-ionic surfactants have been reported. See Kosaka, T; Yamada T. in Sucrochemistry ACS Symposium Series, No. 41; John L. Hickson, Ed.; Am. Chem. Soc.: Washington, D.C., 1977, p 84; James, C. E.; Hough, L.; Khan, R. Prog. Chem. Org. Natl. Products 1989, 55, 117; and Kunz, M. in Carbohydrates as Organic Raw Materials. F. W. Lichtenthaler, Ed.; VCH: Weinheim, 1991, p 127. There has been a rapidly increasing demand for green surfactants, especially for those containing sulphate group(s).
Conventionally, most of the chemists use protected cyclic sulfites to prepare corresponding cyclic sulphates via oxidation, in which the starting compounds do not have free primary hydroxyl group or such group needs to be protected before the oxidation. See Hiyas A. Sayyed et al., Tetrahedron 61 (2005) 2831-2838. It is necessary to remove the protection group to free a hydroxyl group for further reaction. For the cyclic sulfites containing primary hydroxyl groups, there is as yet no one-step-process of converting them into the corresponding cyclic sulphates with high yield, simultaneously without affecting the hydroxyl groups. Thus, there is still a need for an improved process to prepare cyclic sulphates.